Means for focusing for use in connection with film-cameras.



E. E.l HARPER.

MEANS FOR FOCUSING FOR USE IN CONNECTION WITH FILM CAMERAS.

APPLICATION FILED MAY 28. I9I4.

1,243,934. Patented om.. 23,1917.

` y A UNITED y sTATEs PATENT OFFICE.

EDWIN FRANCIS HARPER., VF HARBOBNE, BIRMINGHAM, EZNI'GI'JANID..Y

To :all whom rt may concern Britain, residing at Fenwick House, 4IJordsvwood Road, Harborne, Birmingham, 1n the `county of Warwick,England, accountant.

MEANS Fon. rocUsINc ron USE Y f vBe it known that I, EDWIN FRANcIs HAR-PER, a subject of the Kingdom of Great have invented a certain new orImproved Means for Focusing for Use in Connection with Photographic-FilmCameras, of which the following is a specification.

This invention comprises new or improved means for focusing for use inconnection with photographic roll film cameras, and is particularlyapplicable to that type of camera known as a pocket folding camera inwhich the film of sensitized material is passed from one roller toanother across the rear portion of the camera, the object of thisinvention being to considerably facilitate and expedite the operation offocusing, and enable such focusing to be effected with absoluteexactitude and accuracy for any desired distance.

According to the present invention a focusing screen adapted to beautomatically 'inserted into and displaced from the plane or positionnormally occupied by the film isprovided for use in connection with afilm which is of such a character as to enable focusing to be effectedwithout necessitating the removal of said film from its position infront of the focusing screen.

The movement of the focusing glass member or screen into position forfocusing is advantageously automatically effected by the action ofopening or extending a folding hood or screen, the closing or folding ofsaid hood automatically returning the focusing glass to its normalposition.

In order that this invention may be clearly understood and more readilycarried into practice, reference may be had to the appended explanatorytwo sheets of drawings upon which l Figure 1 is a front or interior viewin perspective of the rear portion ofa film camera illustrating thefocusing means according to the present invention incorporatedtherewith.

Fig. 2 is a rear view in perspective of the arrangement illustrated inFig. 1.

Fig. 3 is a sectional elevation lillustrating one Vmethod of moving thefocusing glass member into the plane normally occupied by the film. f

lFig. 4 is a sectional elevation illustrating Specification of LettersPatent.

IN CONNECTION WITH` FILM-CAMERAS.

Patented oet. 23, 1917.

.Application mea may 2s, 1914. serial No. 344,602.

the focusing glass member in the retracted ornormal position.

Fig. 5 is an enlarged detail view of a part of Fig. 3, showing moreclearly the action of the device.

In a convenient embodiment of this invention within the rear portion a.of the casing of a roll film folding camera, an opening al is formedadvantageously of rectangular formation in focusing -alinement with thelenses which are disposed at the front of the extensible bellows portionin any suitable or usual manner. In this opening al a suitable portionor plate I) of frosted glass, ground glass or other suitable material,assembled within any suitable frame b2, is mounted by means Aof a stripor strips of elastic or resilient material or in any other movablemanner so as to allow the frosted glass or focusing member b to bepressed inward from the plane of the rear casing member a, butautomatically returned and retained in normal position.

Before this focusing member b the photographic film is adapted to pass,it being understood that the specific form of film described herein isnot claimed by me, said form of film being shown in the patent toAlbrecht, No. 687,184, patented November 26, 1901. In order to permitthe focusing to be effected without any obstruction being caused by thefilm, this film may be constituted or composed of alternately sensitizedportions and non-sensitized portions, and each of the non-sensitizedportions is advantageously furnished with an aperture of circular orother formation, so that in focusing, one of the apertures in thenon-sensitized portions is wound or otherwise brought into positionbefore the frosted glass member Z), and a clear unimpeded way is thusfurnished between the lens and the said focusing glass member b and thebellows portion may be readily extended or contracted to bring the imageinto proper focus onto the glass member.

It is not however necessary that the film should be composed ofalternately sensitized and non-sensitized portions, as the said film maybe wholly sensitized or of the usual type and have apertures of anydesired formation furnished therein at suitable positions along thelength of same.

The focusing is rendered absolutely accurate and exact by causing thefocusing member b to be inserted or disposed in posillO the cameracasing a which hood d may advantageously comprise a plurality of flapdoors or like members, say for instance four aps which are adapted to beextended out at right angles to the face of the casing a so as to form aprojecting box-like member forming an effective screen or shade to theeyes when in the act of focusing,

The fiap or cover members l advantageously surround the focusing memberZ) and aie conveniently mounted or hinged in such a manner that whensame are extended out from the casing they cause the focusing member tobe pressed inward into the casing and retained in position in the planenormally occupied by the film c. The closing of the flaps or covers Zcauses the focusing member b to again return to its normal position, andthe said flaps when closed are folded one over tlie other so as toprevent any light from entering the camera casing through the focusingglass member.

In one method of automatically moving or adjusting the focusing glassmember b, the hood or screen fiaps or covers ai may be hinged or pivotedto the casing a and may have small projections Z1 upon their hingededges adapted to engage with or press against the glass member b or itsframe b2 when the flaps l are moved on their hinges so as to extendsame, said projections Z1 causing the glass member b to be pressed andretained in the plane of the film c. The closing of the hood flaps dallows the return of the glass member to its normal position either byyresilient or elastic material or members or by directly fixing the saidglass member to the flaps.

Advantageously spring wires c may be suitably incorporated at the upperand lower edges of the focusing member b or frame b2 surrounding sameand running alongside or parallel with said edges, theI spring wirebeing secured midway of its length and engaging at each extremity with asuitable small pin or projection upon the edges of the frame b2, so asto normally hold the focusing member b and frame in its retractedposition within the aperture a1 in the rear of the casing a.

The focusing member together with hood d are advantageously secured inposition by means of the outer frame portion b1, which is screwed orotherwise 'secured upon the outer or rear face of the casing a. Theframe b1 is conveniently yprovided with in- Wardly projectin pins orprojections b3 at each corner, whic pins are adapted to engage with orare inserted within corresponding apertures Within the corner of theframe b2 of the focusing member b.

The -frame b2 of the focusing member b is conveniently of the usualchannel formation the frosted glass being assembled within saidchannels. The pins b3 upon the frame b1 are advantageously provided withheads, which heads are adapted to slide within the apertures in thecoi'ners of the frame b2 when the focusing member b is pressed inwardfor focusing, but come into engagement with or butt against the rearfiangc of the channel frame b2 or a suitable member or portion thereofso as to prevent the' said frame with the frosted glass I) fiom beingcompletely removed from said projecting pins b3 and at the saine timedetermining the distance to which the member can be displaced.

The assembling and operation of the focusing glass member b may howeverbe otherwise suitably arranged or provided for, so long as the sameresult is effected.

It is readily understood that when the focusing has taken place and thefocusing vglass member returned to its normal position and the focusingscreen folded, the film is wound until one of the sensitized orimperforate portions is in tlie position previously occupied by thefocusing glass member, the focusing having been effected in an accuratemanner.

What I claim as my invention and desire to secure by Letters Patent isl. A photographic camera adapted to use roll films comprising incombination, a movable focusing screen, a folding focusing hood, meanswhereby said movable foolising screen is displaced from its normalposition to the position normally occupied by the sensitized portion ofsaid film by the opening of said focusing hood.

2. A photographic camera adapted to use roll films comprising incombination, a movable focusing screen disposed at the rear of thecamera, a plurality of hinged fiaps forming a folding focusing hood,projections on said hinged flaps adapted, when said focusing hood isextended, to engage said movable focusing screen and displace it intothe normal plane of the film during the focusing operation.

In witness whereof I have hereunto set my hand in the. presence of twowitnesses.

EDWIN FRANCIS HARPER.

Vitnesses:

LEWIS D. COOKE, `ARTHUR H. BROWN.

